/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alipay.sofa.common.xmap;

import java.lang.reflect.Method;

/**
 *
 * @author xi.hux@alipay.com
 * @since 2.6.0
 */
public class XMethodGetter implements XGetter {

    /**
     * method
     */
    private Method   method;

    /**
     * class
     */
    private Class<?> clazz;

    /**
     * bean name
     */
    private String   name;

    public XMethodGetter(Method method, Class<?> clazz, String name) {
        this.method = method;
        this.clazz = clazz;
        this.name = name;
    }

    /**
     * @see XGetter#getType()
     */
    public Class<?> getType() {
        if (method == null) {
            throw new IllegalArgumentException("no such getter method: " + clazz.getName() + '.'
                                               + name);
        }

        return method.getReturnType();
    }

    /**
     * @see XGetter#getValue(Object)
     */
    public Object getValue(Object instance) throws Exception {
        if (method == null) {
            throw new IllegalArgumentException("no such getter method: " + clazz.getName() + '.'
                                               + name);
        }

        if (instance == null) {
            return null;
        }
        return method.invoke(instance, new Object[0]);
    }

}
